Chapter 19 Flashcards
What is the average interval between oestrus periods in the bitch?
7 months
Describe the hormonal changes (and sites of secretion) that cause oestrus
Initiated by increasing concentration of GnRH (hypothalamus)
Subsequent release of FSH and LH from the pituitary - stimulate follicular growth and production of oestrogen
Raised plasma oestrogen => pro-oestrus
Decline in oestrogen and slight increase in progesterone => oestrus
Low oestrogen:progesterone => LH surge => ovulation
Ovulation creates corpus luteum => progesterone
Elevation in progesterone => dioestrus
What are the differences/similarities between the pregnant/non-pregnant luteal phase?
Both have similar progesterone secretion - from corpus luteum
CL maintained by prolactin
How does oestrus differ in the queen?
Polyoestrus
Ovulation induced by coitus
Cyclicity influenced by photoperiod
How is ovulation triggered in the queen?
Copulation = LH surge
Usually multiple needed
When are neutrophils seen on vaginal cytology?
Anoestrus ++
Pro-oestrus +
Early oestrus -
Oestrus +
Dioestrus ++++
When is mucus seen in the oestrus cycle?
NOT during oestrus
How can pregnancy be diagnosed in dogs based on blood tests?
Relaxin - increases at 24 days post ovulation
Fibrinogen/CRP
Progesterone - no value on own, useful in combination with APP
Prolactin (not commonly used)
Where is testosterone produced in male dogs and what regulates it’s secretion?
LH stimulates leydig cells
Which cells produce sperm? What regulates it?
Sertoli cells - stimulated by FSH
